The present invention relates to a specimen preparation device.
A specimen preparation device (ion beam processing device) that utilizes an ion beam is known as a device that prepares a cross section of a specimen that is observed or analyzed using an electron microscope, an electron probe microanalyser (EPMA), an Auger microprobe, or the like.
For example, Japanese Patent No. 4922632 discloses a specimen preparation device that prepares a cross section of a specimen by covering part of the specimen with a shield material, and milling part of the specimen that is not covered with the shield material by applying an ion beam to the specimen (including the edge of the shield material) (from the side where the shield material is provided).
Such a specimen preparation device is designed so that the ion beam is applied to the specimen in a vacuum chamber. In this case, the ion beam that has passed by the specimen without being applied to the specimen may be applied to the inner bottom surface of the vacuum chamber, and the inner bottom surface of the vacuum chamber may be sputtered to contaminate the specimen. The above problem is described below with reference to the drawings.
FIGS. 13 and 14 are views schematically illustrating a state inside a vacuum chamber of a specimen preparation device.
As illustrated in FIG. 13, an ion beam generated by an ion beam generator 4 is applied to a specimen 2 that is partially covered with a shield plate 6. The area of the specimen 2 that is not covered with the shield plate 6 is thus mill to prepare a cross section of the specimen 2.
As illustrated in FIG. 14, when the ion beam is applied to an inner bottom surface 8 of the vacuum chamber after the specimen 2 has been mill, the inner bottom surface 8 of the vacuum chamber is sputtered, and the material that forms the inner bottom surface 8 of the vacuum chamber adheres to a surface 2a (i.e., the surface of the specimen 2 opposite to the surface on which the shield plate 6 is placed) of the specimen 2. As a result, the surface 2a of the specimen 2 is contaminated.
Specifically, a known specimen preparation device has a problem in that the surface 2a of the specimen 2 may be contaminated, and it may be impossible to observe both the cross section and the surface of a single specimen, for example.